There is need for fast and accurate methods and apparatus for measuring tire pressure. The following patents and published applications illustrate the efforts of others to address the problems identified and solved by the disclosure herein. As can be seen, there are a vast array of efforts already existing to provide a solution to the problems confronted when measuring tire pressure, but none provides the combination of features and advantages presented in the instant disclosure.
These references include: U.S. Pat. No. 7,882,732 entitled “Apparatus for Monitoring Tire Pressure,” was issued to Haralampu, et al. on Feb. 8, 2011; U.S. Pat. No. 7,817,024, entitled “Vehicle Tire Warning System,” was issued to Ru on Oct. 19, 2010; U.S. Pat. No. 7,555,931 entitled “Non-destructive Testing of the Lining of a Process Vessel,” was issued to Palmer on Jul. 7, 2009; U.S. Pat. No. 6,959,594 entitled “External Mount Tire Pressure Sensor System,” was issued to Huang on Nov. 1, 2005; U.S. Pat. No. 6,748,791 entitled “Damage Detection Device and Method,” was issued to Georgeson, et al. on Jun. 15, 2004; U.S. Pat. No. 6,736,004 entitled “Ultra-wide Band Soil/Tire Interaction Radar,” was issued to Evans, et al. on May 18, 2004; U.S. Pat. No. 6,343,506 entitled “Tyre Pressure Determination,” was issued to Jones, et al. on Feb. 5, 2002; U.S. Pat. No. 6,339,960 entitled “Non-intrusive Pressure and Level Sensor for Sealed Containers,” was issued to Costley, et al. on Jan. 22, 2002; U.S. Pat. No. 5,962,779 entitled “Method for Determining Tire Inflation Status,” was issued to Bass on Oct. 5, 1999; U.S. Pat. No. 5,837,897 entitled “Testing Vehicle Tires,” was issued to Jones, et al. on Nov. 17, 1998; U.S. Pat. No. 5,117,835 entitled “Method and Apparatus for the Measurement of Intracranial Pressure,” was issued to Mick on Jun. 2, 1992; U.S. Pat. No. 4,996,516 entitled “Indicator of Under Inflated Tire,” was issued to Mason on Feb. 26, 1991; U.S. Pat. No. 4,630,470 entitled “Remote Sensing of Vehicle Tire Pressure,” was issued to Brooke, et al. on Dec. 23, 1986; U.S. Pat. No. 4,479,386 entitled “Insulation Bonding Test System,” was issued to Beggs, et al. on Oct. 30, 1984; U.S. Pat. No. 4,089,226 entitled “System for Residual Tire Life Prediction by Ultrasound,” was issued to Kraska, et al. on May 16, 1978; U.S. Patent Application Publ. No. 2002/0038570 entitled “Remote Pressure Indicator for Sealed Vessels Including Vehicle Tires,” was applied for by Burns on Aug. 2, 2001; U.S. Patent Application Publ. No. 2009/0315694 entitled “Piezoelectric Triggering Mechanism,” was applied for by Sinnett, et al. (as a PCT) on Mar. 14, 2006; and U.S. Patent Application Publ. No. 2010/0089161 entitled “Vibration Based Damage Detection System,” was applied for by Taheri (as a POT) on Feb. 15, 2008.
These references are discussed in greater detail as follows.
U.S. Pat. No. 7,882,732 generally discloses an apparatus for monitoring the pressurization in a tire. The device has a magneto-mechanical pressure sensor in or on the tire and an electromagnetic excitation system. The electromagnetic excitation system interrogates the magneto-mechanical pressure sensor. The apparatus also has a receiver. The receiver receives information from the electromagnetic excitation system. The apparatus also has a data interpretation system for translating the received information into the tire pressurization state. The data interpretation system is connected to a display, which communicates the tire pressurization state to an operator. Thus, an apparatus for monitoring tire pressure in a tire 12 has magneto-mechanical sensors 20 embedded in or on tire 12 and an exciting system 22 external to the tire 12, as disclosed in FIGS. 1-2, 11-13, and further at Col. 8 Line 61 to Col. 10, Line 18; Col. 11, Line 3 to Col. 12, Line 3 and in Claims 1-2, 5 and 7-10.
U.S. Pat. No. 7,817,024 generally discloses an air pressure sensor (2) for a vehicle tire warning system includes a tubular housing (21) defining a chamber (218). An air pressure actuating device is seated in the chamber and is moveable back and forth in the chamber in response to air pressure change in the vehicle tire. A switch device to electrically connect a high air pressure warning circuit or a low air pressure warning circuit operates under the drive of the air pressure actuating device. The chamber of the tubular housing is communicated to the atmosphere via a connecting pipe (29).
U.S. Pat. No. 7,555,931 generally discloses a process for the non-testing of a refractory lined process vessel including the steps of: (a) striking an external wall of a process vessel internally lined with a refractory material with an impulse hammer; (b) measuring selected frequency characteristics of the refractory lined process vessel; and (c) analyzing the measured frequency characteristics and determining the integrity of the internal lining of refractory material from the measured frequency characteristics. More specifically, nondestructive testing of a pressure vessel includes the steps of: striking the exterior wall of a vessel to generate accelerator frequencies recorded on a data logger, as further disclosed in FIGS. 1-20; Col. 5, Line 29 to Col. 6, Line 40 and in Claims 1-7, 11, 13, 15-28 and 30-31.
U.S. Pat. No. 6,959,594 generally discloses an external mount tire pressure sensor system with a stretch sensor having a variable resistance longitudinal displacement characteristic. The stretch sensor is coupled to a processor which samples the resistance of the stretch sensor periodically. The sensor body is attached to the external side wall of a pneumatic tire so that the body is displaced by the tire side wall and the resistance is a function of internal tire pressure. When the processor determines that the pressure is below a threshold value, an RF generator is activated by the processor to generate a low tire pressure signal. This signal is converted by a receiver to a warning for the driver.
U.S. Pat. No. 6,748,791 generally discloses a damage detection device used to detect damage in bonded and laminated composite structures. A tap hammer or tap coin containing an acceleration sensor is connected to a circuit that can measure the width of an impact signal and then display the result. The result correlates to local stiffness of a structure. A method of determining the desired signal width and the method of using the damage detection device includes tapping a known good region and then tapping a suspect region. Readings from the two areas are used to determine whether the suspect region is within an acceptable range. The circuit determines the desired signal width by measuring from the time the impact signal exceeds a threshold to the time it falls below the threshold. Thus, an inspection device includes a hand-held hammer 10, 12, with an accelerator 13, connected to an oscilloscope and read out display 18. Cf. FIGS. 1-3; Col. 3, Line 50 to Col. 5, Line 29 and Claims 1-5.
U.S. Pat. No. 6,736,004 generally discloses a radar system for vehicle tire testing and analysis. The system may be mounted within the casing of a vehicle tire to measure the location of the inner casing of the tire (tire deformation) as well as the location of the tire/soil interface (tire footprint). The radar system may also be used to determine soil characteristics by analyzing the reflected signals. The system may have particular use in testing tires for use with on- or off-road surfaces. The system may also be used to monitor tire deformation, traction, footprint, and soil characteristics.
U.S. Pat. No. 6,343,506 generally discloses a method and apparatus for determining tire pressure in automotive vehicles. The apparatus uses twin spaced parallel and non-transverse piezoelectric cables which are traversed by a vehicle to produce a voltage pulse having a shape or profile characteristic of the tire pressure. Waveform analysis on the basis of a software algorithm and/or look-up calibration data enables numerical pressure determination. The system is adapted for remote automotive vehicle tire pressure sensing under normal conditions of vehicle use.
U.S. Pat. No. 6,339,960 generally discloses a method and apparatus for determining the internal pressure of a sealed container. The method includes: first, exciting a lid of the container so as to create at least two modes of vibration having separate frequencies, wherein said frequencies are fundamental, f1, and a second frequency, preferably the second axi-symmetric mode, f2. Next, the vibration resulting from said exciting is detected to determine f1, and f2. Then, f2, which is indicative of internal pressure, is used to calculate a first value for internal pressure using a first mathematical model that is calibrated to the lid on the sealed container. Then, f1, which is indicative of volume of contents, is used to calculate the volume of contents in the sealed container using a second mathematical model that is calibrated to the lid on the sealed container, wherein a natural frequency of said lid is a function of said internal pressure and said volume of contents. Next, the volume of contents is compensated for to determine a second value for internal pressure, in which the second value for internal pressure is more reliable than said first value for internal pressure. The apparatus for determining the internal pressure of a sealed container of the invention includes: means for exciting a lid of the container so as to create at least two modes of vibration having separate frequencies, wherein said frequencies are fundamental, f1, and a second frequency, preferably the second axi-symmetric mode, f2; detecting means for detecting vibration resulting from the exciting of said container to determine f1, and f2 calculating means for calculating a first value for internal pressure of said container using f2; calculating means for calculating the volume of contents of said container using f1; wherein a natural frequency of said lid is a function of said internal pressure and said volume of contents; and calculating means for compensating for said volume of contents to determine a second value for internal pressure, wherein said second value for internal pressure is more reliable than said first value for internal pressure. Thus, a non-intrusive pressure sensor for sealed containers is disclosed. The sensor includes an accelerometer 2 connected to the lid of a pressure container with an impulse from an impact hammer producing a frequency 7 and calibrated to read vessel internal pressure. More detail is disclosed in FIGS. 5 A-E; Col. 7, Line 1 to Col. 8, Line 31 and in Claims 1-6.
U.S. Pat. No. 5,962,779 generally discloses a method and device for determining the inflation status of a vehicle tire while the tire is installed on the vehicle. A first signal is recorded representing the weight (Y) on a scale plate with respect to time when the tire is rolling on the scale plate. A second signal is recorded representing the weight (X) on a deformation bar with respect to time when the tire is rolling over the deformation bar. The maximum Y of the first signal and the maximum X of the second signal are determined. A ratio R is calculated by dividing the maximum X of the second signal by the maximum Y of the first signal. The calculated ratio R (=X/Y) is compared with a predetermined value for the ratio R pertaining to the maximum Y of the first signal. Apparatus is provided to give an under-inflation signal if the calculated ratio is below the predetermined value. Predetermined values for the ratios are obtained by determining, for a large number of combinations of vehicles and tires, the ratio R as a function of tire pressure. A threshold is calculated for each combination of vehicles and tires. A curve is fitted of predetermined values for the ratios R through points having as coordinates the corresponding maximum value Y of the weight on the scale plate with respect to time when the tire is rolling on the scale plate and the corresponding ratio pertaining to the threshold. The curve of predetermined values is fitted so as to define a smooth curve that is an envelope which lies below all threshold data but is as close to the data as possible. Thus, a tire inflation status apparatus comprising an impact means 20, load cells 14, 40, and computer 60 is disclosed. See FIGS. 1-3: Col. 3, Line 41 to Col. 5, Line 37 and Claims 1-4.
U.S. Pat. No. 5,837,897 generally discloses a method and apparatus for testing inflated vehicle tires to determine internal physical characteristics such as tire pressure. The apparatus includes a waveform transceiver that subjects a tire to be tested to a transmitted waveform. The transceiver also transmits an ultrasonic waveform from a location external to the tire under test. Additionally, the transceiver receives the ultrasonic waveform from a tire under test at a location external thereto. A processor is provided for interpreting the received waveform with reference to the decay or attenuation of the amplitude of the waveform with time to provide a measure of the internal physical characteristic. Thus, a vehicle tire testing apparatus is disclosed having an ultrasonic transducer 14 external to the wall 28, a processor and a display 29, as more fully shown in FIGS. 1, 5 and 6; Col. 4, Line 6 to Col. 5, Line 26 and Claims 1-5.
U.S. Pat. No. 5,117,835 generally discloses a method and apparatus for non-invasively measuring changes in intracranial pressure (ICP) in a patient's skull which allow trends in such pressure to be diagnosed over time. A generation of a predetermined vibration signal is applied to a first location on a skull. An output vibration from another location on the skull is detected. Data characteristics of the two signals are stored. These steps are repeated and the data is analyzed to diagnose changes in ICP over time.
U.S. Pat. No. 4,996,516 generally discloses an indicating device adapted to indicate a severely underinflated tire. The device is activated by the enlargement in the diameter of the underinflated tire caused by centrifugal force acting on the tread, and may be especially useful on dual wheels, although it will work on others as well. The device includes a contact device which is contacted by an expanding tire. That contact tilts a switch to cause a circuit to be completed to light a signal lamp in the cab of the truck.
U.S. Pat. No. 4,630,470 generally discloses apparatus and a method for determining the tire pressures of vehicles as they pass an instrumented checkpoint on a roadway. Rigid corrugations on the roadway set the tires into vibration with a waveform which is a function of tire pressure. The complex waveforms from each tire of a given vehicle are subjected to a spectral analysis and the results of such analyses are compared to each other to determine which, if any, of said tires have produced a spectrum different from the normal spectra produced by the other tires. Thus, no apparatus mounted on the vehicles is being checked. A vehicle tire 19 pressure sensor 25 has energy impulse means which are instrumented to produce mechanical vibration wave forms. A processor 29 to measure the tire pressure is disclosed, as shown in FIGS. 2-5; Col. 3, Line 23 to Col. 5, Line 32; Col. 6, Lines 1-22 and Claims 1 and 5-6.
U.S. Pat. No. 4,479,386 generally discloses a method and a system for testing the bonding of foam insulation (22) attached to metal. The system involves the use of an impacter (10) which has a calibrated load cell (12) mounted on a plunger (14), and a hammer head (16) mounted on the end of the plunger (14). When the impacter (10) strikes the insulation (22) at a point to be tested, the load cell (12) measures the force of the impact and the precise time interval during which the hammer head (16) is in contact with the insulation (22). This information is transmitted as an electrical signal (20) to a load cell amplifier (28) where the signal (20) is conditioned and then transmitted to a Fast Fourier Transform (FFT) analyzer (34). The FFT analyzer (34) produces energy spectral density curves (power plotted against frequency in Hertz) which are displayed on a video screen (39). An operator, by observing the frequency point at which the curve terminates, may determine the quality of the bond. Specifically, the termination frequency of the energy spectral density curve may be compared with a predetermined empirical scale to determine whether a high quality bond, good bond, or debond is present at the point of impact. For future reference and use, data from the FFT analyzer (34) are recorded on a magnetic disk (41) and/or a hard copy is produced by a printer (43) system.
U.S. Pat. No. 4,089,226 generally discloses a residual tire life prediction system. The system uses a clock to trigger a bang generator that provides pulses of electrical energy to a pulse-echo transducer. The transducer converts pulses of electrical energy to pulses of ultrasonic vibration. The transducer is located on the tread of a steel belted tire to transmit pulses of ultrasonic energy into the tire and to receive reflected ultrasonic energy from plies of the tire casing. The transducer converts the reflected ultrasonic energy to provide bursts of electrical signals. The transducer is connected to a time varying gain control circuit that has its output connected via a full-wave rectifier to a first gate and to an input of a voltage level detector. The clock is also connected to a first time-delay circuit that is operative after a delay, subsequent to the pulse of the bang generator, to enable a second gate. This is connected to the output of the voltage level detector that provides a signal when it receives the signal based on the reflection from the outer steel belt. This is relayed to a second time-delay circuit that provides an enable signal at its output after a predetermined delay for a predetermined period of time to the first gate. This opens the first gate for passage of signals from the rectifier to a peak sensing device that provides an output signal to a digital panel meter for display of the value of the maximum amplitude passing through the first gate. Thus, the system includes a pulse-echo transducer 11, bang generator 17 and amplifier circuit 20 as shown in FIGS. 1 and 2; Col. 6, Line 31 to Col. 8, Line 41, and Claims 1-5 and 17.
U.S. Patent Application Publ. No. 2002/0038570 generally discloses a compact, robust, and inexpensive magnetically coupled pressure gauge. The gauge includes a spiral-faced or helical bellows coupled for rotating a magnetic field source (permanent magnet) within a pressure vessel. The orientation of the magnetic field is externally sensed and correlated to pressure within the pressure vessel. Applications contemplated include measuring pressure in pressure vessels and pressure of pneumatic vehicle tires without breaching the integrity of the particular pressurized vessels. Embodiments included a visual, manual tire pressure monitoring system.
U.S. Patent Application Publ. No. 2009/0315694 generally discloses a piezoelectric triggering mechanism (10) includes a piezoelectric element (12), such as the transducer of a SAW device, that is configured to crack or break upon being subjected to excessive levels of mechanical force or other triggering mechanisms, thus generating a burst of electromagnetic energy. The large impulse of energy can then be conditioned (14) through resonant circuits or antennae and modulated (16) with an identification pattern through appropriate structures (such as SAW electrodes) to send a breakage indication signal to a remote receiver (18). Piezoelectric elements (12) may be integrated with a pneumatic tire structure to provide indication upon pressure loss or tire failure. Piezoelectric elements (12) may also be integrated with safety support features of some tire structures to provide indication of tire operation in a run-flat mode of operation. Related aspects of the present piezoelectric triggering technology employ a piezoelectric element (12) in a trigger detection method, which may involve detection of such occurrences as breach of security via opening of a sealed access structure or breakage of a glass panel, deployment of an airbag, loss of pressure or excess deflection in a tire, presence of smoke in a given location, and other rupture and sensor applications.
U.S. Patent Application Publ. No. 2010/0089161 generally discloses methods to assess damage on a joint. These include energizing the joint, detecting the vibration of the joint using one or more signal generating sensors, processing the signal(s), and applying a damage index to the processed signal(s). The damage index incorporates a processed control signal generated by a sensor(s) at or near the joint when the joint was healthy, i.e., in a substantially undamaged state. In another embodiment, a pipeline having at least two pipe segments and at least one joint connecting the two pipe segments is provided. At least one signal generating sensor is affixed to the pipeline and is capable of detecting vibration at or near the joint. At least one signal processor capable of EMD processing the signal is provided. An output device (e.g., computer monitor, LED display, a light bulb, an electronic alarm, or other sound or light generating device) is provided. Thus, a piezoelectric sensor with accelerometer capable of detecting an impulse hammer measurable response is disclosed, as described in FIGS. 1-3; Paragraphs [0011]-[0025], [0081]-[0082] and Claims 1, 15, 21 and 27.
Thus, a problem associated with devices that precede the present disclosure is that they do not provide, in combination with the other features and advantages disclosed herein, a tire pressure measuring system that is self-contained and may be conveniently used by a single operator, without special devices or sensors attached to the tire or a need to analyze data obtained from these devices or sensors, as is done in typical modal analyses, in order to determine the tire pressure.
Yet another problem associated with devices that precede the present disclosure is that they do not provide, in combination with the other features and advantages disclosed herein, a tire pressure measuring system that does not require special modification of the roadway to measure tire pressure.
Still a further problem associated with devices that precede the present disclosure is that they do not provide, in combination with the other features and advantages disclosed herein, a tire pressure measuring system that does not require access to, or even location of, the tire valve as is required when using pencil type, digital strain type or Bourdon tube type gauges.
An additional problem associated with devices that precede the present disclosure is that they do not provide, in combination with the other features and advantages disclosed herein, a tire pressure measuring system that does not require special devices or sensors mounted on the vehicle, the vehicle wheel well, the vehicle wheel, or the tire.
Another problem associated with devices that precede the present disclosure is that they do not provide, in combination with the other features and advantages disclosed herein, a system to measure tire pressure that provides precise pressure data rather than reporting simply if the tire is sufficiently inflated or not.
An even further problem associated with devices that precede the present disclosure is that they do not provide, in combination with the other features and advantages disclosed herein, a tire pressure measuring system that is impervious to damage from road conditions upon which the vehicle rests or travels.
Still another problem associated with devices that precede the present disclosure is that they do not provide, in combination with the other features and advantages disclosed herein, a tire pressure measuring system that insensitive to ballast that may be in the tire, for instance that which is often found in tires used for agricultural applications.
A yet further problem associated with devices that precede the present disclosure is that they do not provide, in combination with the other features and advantages disclosed herein, a tire pressure measuring system that is simple to calibrate for a variety of types and sizes of pneumatic tires.
And yet another problem associated with devices that precede the present disclosure is that they do not provide, in combination with the other features and advantages disclosed herein, a tire pressure measuring system that does not require seating it on a tire valve.
A still further problem associated with devices that precede the present disclosure is that they do not provide, in combination with the other features and advantages disclosed herein, a tire pressure measuring system that provides excellent display resolution and is easy to read.
A further problem associated with devices that precede the present disclosure is that they do not provide, in combination with the other features and advantages disclosed herein, a tire pressure measuring system that provides accurate and precise pressure reading over a wide range of pressures.
Another problem associated with devices that precede the present disclosure is that they do not provide, in combination with the other features and advantages disclosed herein, a tire pressure measuring system that does not require a precise impulse to yield a precise measure of tire pressure, merely an impulse that is within the range usually associated with an impact by a hand-held hammer.
There is a demand, therefore, to overcome the foregoing problems while at the same time providing a tire pressure measuring system that is simple and rapid to use by a single operator, while being self-contained and yielding precise and accurate values of tire pressure.